Stoker mechanism



2 Sheets-Sheet 1 ATTORNEY.

5mm 16, 1936. P. A. KETCHPEL STOKER MECHANISM Original Filed Dec. 16,1951 June 16, 1935. p KIETCHPEL 2,@44,3@8

sToKE'R MECHANISM Original Filed Dec. 16, 1931 2 Sheets-Sheet 2INVENTOR.

ATTORNEY.

a I f 53 0/ Patented June 16, 1933 STOKER IVIECHANISM ApplicationDecember 16, 1931, Serial No. 581,314 Renewed May 1, 1936 13 Claims.

This invention relates to locomotive stokers and particularly to stokersof the type effecting a classification of the fuel.

It is one of the objects of the invention to provide new and improvedmechanism in a stoker of the class described for separating thepulverized particles of coal from the coarser particles.

It is a further object of the invention to provide novel and improvedmeans for separately introducing the pulverized fuel particles and thecoarser particles into the firebox in a manner whereby the quantity ofpulverized fuel particles escaping through the fines and out the stackis reduced to a negligible amount.

It is another object of the invention to provide means for separatingthe pulverized fuel particles from the coarser particles and forintroducing the coarser particles into the firebox through theconventional firing opening and the pulverized fuel particles throughopenings in the forward portion of the firebox sidewalls.

A further object of the invention is to provide means for separating thepulverized particles of fuel from the coarser particles, and separatingthe coarser particles into fine and coarse fuel and providing separatemeans for introducing each into the firebox.

A further object of the invention resides in the provision of means forwithdrawing pulverized particles of fuel by suction as the fuel isdelivered to the conventional firing opening and introducing it by apressure blast in the firebox through openings in the forward portion ofthe firebox sidewalls.

Further objects and advantages of the invention consist essentially inthe construction, arrangement, and combination of the various parts, aswill become apparent from the following description when read inconnection with the accompanying drawings, in which Fig. l is a view inside elevation of the rearward portion of a locomotive with the cabremoved and the forward portion of a tender with the invention appliedthereto;

Fig. 2 is a view in longitudinal vertical section of a portion shown inFig. 1 with parts shown in side elevation;

Fig. 3 is a view in rear elevation of the locomotive and stokermechanism with parts broken away and shown in section; and

Fig. 4 is a sectional view on the line 4--4 of Figure 1.

In the drawings the locomotive generally designated by the numeral l0comprises a boiler H, a boiler firebox l2, the grate I3 and a roof orarched cover comprising spaced members l4 and refractory material 15.

The boiler H embodies the backwall l6 having a firing opening I!therethrough, a throat sheet #3 oppositely disposed from the backwalland the sidewalls I 9 and 20.

The locomotive is flexibly connected to a tender, indicated generally at2|, having a stoker fuel transfer conduit 22 extending forwardly frombeneath the tender fuel bin (not shown). A riser conduit 23, which maybe supported from the locomotive frame 24 by suitable means as by theflexible support member 25, is flexibly connected at its lower end tothe forward end of the transfer conduit 22 and extends upwardly andforwardly to the firing opening ll. The upper end portion 26 of theriser conduit 23 flares outwardly providing a wide delivery mouthwhereby the fuel discharged by the riser screw 21 drops from the loweredge or ledge 28 of the fiared end portion 25 in a wide, thin sheet orcurtain-like form.

Formed with the underside of the riser conduit 23 is a casing 29,opening at its upper end into the firing opening immediately beneath thelower edge 28 of the flared portion 26 of the riser conduit. The lowerend of the casing 29 is provided with a pair of diametrically oppositeopenings 39 and 3|. Conduits 32 and. 33 communicate with the casing 29through the elbows 34 and 35, respectively, which connect the conduits32 and 33 with the openings 39 and 3| respectively. The conduits 32 and33 extend downwardly from the elbows, then outwardly to respective sidesof the locomotive, then extend in a generally forward and upwarddirection and enter the firebox l2 through openings 36 and 37 in theboiler sidewalls l9 and 29 respectively, adjacent the throat sheet I8.

A shaft 38 extends transversely through the lower portion of the casing29, one end being supported in the bearing 39 formed in the elbow 35,and the other end extending through and beyond the elbow 3 8. Mounted onthe shaft 38, adjacent the openings 39 and 3! in the casing 29 are thefans 43 and 4| respectively, the fan blades and direction of rotationbeing arranged to create a suction in the casing 29 and issue a pressureblast through the conduits 32 and 33.

The shaft 38 is driven from a turbine motor 42 in order to produce thenecessary speed of rotation of the fans 40 and 4| to create the requiredsuction in the casing 29. The motor 42 is supported from the locomotiveframe 24 by a yieldable member 44. The fuel conveying system of thestoker is operated from its rearward end through a shaft 45 extendingrearward from the motor 42 to the rear of the transfer conduit 22.Gearing at the rear of the trough (not shown) and reduction gearing 45on the locomotive is arranged to provide a predetermined ratio betweenthe speed of rotation of the fans 49 and ll and the speed of rotation ofthe conveyor screws. If the speed of the fuel conveying screw isincreased to deliver more fuel to the firebox the speed of the fans willbe increased, producing the greater suction that is necessary towithdraw the pulverized fuel particles from the increased amount of fuelbeing delivered. Thus, once the proper ratio is determined between thespeed of the fans and the speed of the fuel conveying screw, that ratiois always maintained.

The lower forward edge of the casing 29, preferably terminates in aplurality of diverging fingers 61 which extend beyond the forward loweredge 23 of the casing 29. The fingers 31 are cored and provided with thejet openings 48 for the emission of a pressure fiuid blast. Adistributor plate Q9, slightly below the fingers ll, extends forwardlybeyond the fingers 41. A series of jet openings 50 are arranged at therear of the distributor plate 49 between the plate and the fingers l'i.Supply lines 5| deliver fiuid pressure, such as steam, to the jetopenings 48 and 55.

The forward ends of the conduits 32 and 33 are provided with the nozzles52 and 53 which penetrate the openings 35 and 37 respectively, and arediametrically opposed to one another. The firebox arch is provided witha transverse depending refractory ridge 54 rearward of the nozzles 52and 53 and forming with the throat sheet [8 a subcombustion chamber 55for the pulverized fuel particles issuing from the nozzles 52 and 53.

In operation, fuel is elevated by the riser screw 27 and as it is pushedthrough the flared portion 26 of the riser conduit 23 and over the ledge28 it is spread out in a wide thin sheet. The fuel drops onto the prongsor fingers 41 and as it falls the suction created by the fan blades 40and 4| withdraws the pulverized fuel particles. The coarser particles offuel are not affected by the fan blades ii! and 4| and fall on thefingers 41. Some of the fuel will drop through the spaces between theprongs or fingers 4'1 onto the rear of the distributor plate 49, whencethey are projected over the firebed by the pressure blast issuing fromthe jets 50. The coarser particles of fuel that do not pass through thefingers 41, roll forwardly over them onto the distributor plate 49 andare projected over the firebed by the pressure blast issuing from thejets 48 in the fingers 47. The blast issuing from the jets 43 isarranged to be at a higher pressure than the blast issuing from the jets50, since a blast of greater intensity is necessary to project thelarger particles of fuel to the forward extremities of the firebox thanthe finer particles. The distributor plate 49 may be provided withgrooves, ridges or both in a manner well known in the art to deflectportions of the fuel to the corners of the firebox and to obtain an evendistribution of fuel over the entire firebed.

The pulverized particles of fuel withdrawn by the fans 4E) and ll passbetween the blades and are impelled by the current of air passingbetween the blades through the conduits 32 and 33 into the front of thefirebox. In this manner the pulverized fuel is introduced at the hottestpart of they fire, so that combustion takes place immediately upondelivery to the firebox, greatly minimizing the loss of fuel unconsumedthrough the fiues and out the stack. Other factors aiding to eliminatethe escape of fuel unconsumed, are, the particular arrangement of thenozzles 52 and 5 53 whereby they are diametrically opposed in oppositesidewalls of the firebox and the formation of the sub-combustion chamberby the refractory ridge 54.

I claim:

1. In a locomotive having a firebox provided with a firing opening and afire-arch, a stoker comprising a fuel conduit delivering to said firingopening, the forward portion of said conduit flaring laterally, fueldistributing means at said firing opening arranged to project the fuelpassing from the forward end of said fuel conduit over the fire in saidfirebox, a casing having an opening adjacent the delivery end of saidconduit, a conduit communicating at one end with said casing and at itsother end opening into said furnace at a point beneath said fire-archand remote from said firing opening, and a fan in said casing arrangedto entrain particles of pulverized fuel from the bulk of fuel passingfrom the forward end of said first named conduit to said fueldistributing means, through said casing for ejecting said particles ofpulverized fuel through said second named conduit into said fireboxbeneath the fire-arch.

2. In a locomotive having a firebox provided with a firing opening, astoker comprising a conveyor delivering fuel to said firing opening, acasing subjacent said conveyor opening at its forward end in said firingopening, a distributor plate extending forwardly from beneath theforward end of said casing, a conduit communicating at one end with saidcasing and at its other end opening into said firebox at a point remotefrom said firing opening, means in said casing arranged to entrainparticles of pulverized fuel as the fuel delivered by said conveyordrops onto said distributor plate and arranged to propel saidparticlesof pulverized fuel through said conduit, and means at the rearof said distributor 5 plate for projecting fuel thereover into thefirebox.

3. In a locomotive having a firebox provided with a firing opening, astoker comprising a conveyor delivering fuel to said firing opening, 5 acasing subjacent said conveyor, said casing opening at its forward endimmediately beneath the delivery end of said conveyor, means in saidcasing arranged to entrain particles of pulverized fuel as it falls bygravity from the discharge 55 end of said conveyor, said entrainingmeans being also arranged to propel the entrained particles ofpulverized fuel into the firebox, means beneath the open forward end ofsaid casing arranged to receive and separate the unentrained fuel intofine and coarse particles, means for projecting said fine and coarseparticles into the firebox, and a conduit communicating at one end withsaid casing and at its other end opening into said firebox at a pointremote from said fir- 5 ing opening for delivering said entrainedparticles of pulverized fuel to said firebox.

4. In a locomotive having a firebox provided with a backwall andsidewalls and a firing opening in said backwall, a stoker comprising afuel conduit delivering to said firing opening, the forward portion ofsaid conduit flaring laterally,

a screw in said conduit delivering fuel therethrough cooperating withsaid flaring conduit portion to deliver the fuel therefrom in aflattened stream, a casing subjacent said conduit opening at its forwardend beneath the delivery end of said conduit, an opening in each of saidfirebox sidewalls at points remote from said backwall, a pair of tubularconduits each communicating at one end with said casing and at the otherend with one of said sidewall openings, means in said casing arranged toentrain particles of pulverized fuel from said flattened stream and toproject said particles of pulverized fuel through said tubular conduitsinto the firebox, and means for projecting the unentrained fuel into thefirebox.

5. In a locomotive having a firebox provided with a backwall, a firingopening in said backwall, a fire-arch extending upwardly and rearwardlyfrom the lower forward end of said firebox and terminating short of saidbackwall forming between said fire-arch and said backwall an escapepassage for products of combustion, means for delivering fuel to saidfirebox including means for separating particles of pulverized fuel fromthe bulk of said fuel, means providing a passage between said separatingmeans and said firebox, said separating means arranged to projectparticles of pulverized fuel through said passage into said firebox at apoint beneath said fire-arch and remote from said escape passage andmeans for projecting t e bulk of said fuel into said firebox through thefiring opening in said backwall.

6. In a locomotive having a firebox provided with a grate and abackwall, a firing opening in said backwall, a fire-arch extendingupwardly and rearwardly from the lower forward end of said firebox andterminating short of said backwall forming between said fire-arch andsaid backwall an escape passage for products of combustion, means fordelivering fuel to said firebox including means for separating particlesof pulverized fuel from the bulk of said fuel, means providing a passagebetween said separating means and said firebox, said separating meansarranged to project the particles of pulverized fuel through saidpassage into said firebox at a point between said fire-arch and saidgrate and remote from said escape passage and means for projecting thebulk of said fuel into said firebox through the firing opening in saidbackwall.

'7. In a locomotive having a firebox provided with a fire-arch and withwalls, an opening in one of said walls, an opening in another of saidwalls at a point directly beneath said fire-arch and separated from saidfirst named wall, a grate for said firebox, fuel distributing means atthe first named opening above the level of the grate, means for urgingfuel to a point adjacent said distributing means and delivering the samefrom such point into the zone of action of said distributing means forprojection over the grate, means acting on the fuel during the passagethereof from said point to said zone to separate fine particles of fuelfrom the bulk thereof, means providing a passage between said separatingmeans and said second named opening, said separating means arranged toproject such separated fine fuel through said passage into the fireboxthrough the second named opening.

8. In a locomotive having a firebox provided with a firing opening inthe backwall thereof, a fire-arch and grates, fuel distributing means atsuch opening above the level of the grate, means for urging fuel to apoint adjacent said distributing means and delivering the same from suchpoint into the zone of action of said distributing means for projectionover the grate, means arranged toientrain the particles of fine fuelfrom the bulk thereof during passage thereof from such point to saiddistributing means, and means providing a passage between saidentraining means and said firebox at a point adjacent the front endthereof, such entraining means being also arranged to eject theentrained fine particles of fuel through said passage into the fireboxadjacent the front end thereof and beneath said fire-arch.

9. In a furnace provided with a firing opening and a grate, a stoker forsupplying fuel to said furnace including conveying means for urging fuelto a point of discharge at said firing opening, fuel distributing meansat said firing opening in spaced relation With the point of fueldischarge, said conveying means urging all the fuel toward the point ofdischarge for passage therefrom toward the distributing means, meansarranged to entrain the particles of fine fuel from the bulk thereofduring passage of the fuel from the point of discharge toward saiddistributing means and prior to action of said distributing means on thefuel, and means providing a passage between said entraining means andsaid firebox, such entraining means being also arranged to eject theentrained particles of fuel through said passage into the firebox out ofthe zone of action of said distributing means.

10. In a furnace provided with a firing opening and a grate, a stokerfor supplying fuel to said furnace including conveying means for urgingfuel to a point of discharge at said firing opening, fuel distributingmeans at said firing opening in spaced relation with the point of fueldischarge, said conveying means urging all the fuel toward the point ofdischarge for passage therefrom toward the distributing means, meansarranged to entrain the particles of fine fuel from the bulk thereofduring passage of the fuel from the point of discharge toward saiddistributing means and prior to action of said distributing means on thefuel, means providing a passage between said entraining means and saidfirebox, such entraining means being also arranged to eject theentrained particles of fuel through said passage into the firebox out ofthe zone of action of said distributing means, and a motor forsimultaneously operating said fuel conveying means and the fuelentraining and e ecting means.

11. In a locomotive having a firebox provided with a backwall, a firingopening in said backwall, a fire-arch extending upwardly and rearwardlyfrom the lower forward end of said firebox and terminating short of saidbackwall forming between said fire-arch and said backwall an escapepassage for products of combustion, means for delivering fuel to saidfirebox including means for separating particles of fine fuel from thecoarse fuel, means providing a passage for the delivery of the separatedparticles of fine fuel from said separating means to said firebox, saidpassage opening into said firebox at a point beneath said fire-arch andremote from said escape passage and means for projecting the coarse fuelinto said firebox through the firing opening in said backwall.

12. In a locomotive having a firebox provided with a grate and abackwall, a firing opening in said backwall, a fire-arch extendingupwardly and rearwardly from the lower forward end of said firebox andterminating short of said backwall forming between said fire-arch andsaid backwall an escape passage for products of combustion, means fordelivering fuel to said firebox including means for separating particlesof fine fuel from the coarse fuel, means providing a passage for thedelivery of the separated particles of fine fuel from said separatingmeans to said firebox, said passage opening into said firebox at a pointbetween said fire-arch and said grate and remote from said escapepassage and means for projecting the coarse fuel into said fireboxthrough the firing opening in said backwall.

13. In a locomotive having a firebox provided with a backwall, means fordelivering fuel to said firebox having a discharge and adjacent saidbackwall, a fire-arch extending upwardly and rearwardly from the lowerforward end of said firebox and terminating short of said backwallforming between said fire-arch and said backwall an escape passage forproducts of combustion, said fuel delivering means including means forseparating particles of fine fuel from the coarse fuel, means providinga passage for the delivery of the separated particles of fine fuel fromsaid separating means to said firebox, said passage opening into saidfirebox at a point beneath said firearch and remote from said escapepassage and means adjacent said backwall for projecting the coarse fuelover the firebed in said firebox.

PAUL A. KETCHPEL.

CERTIFICATE OF sme ma Patent No. 2,044,508. June 16, 1936.

PAUL A. KETCHPEL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,first column, line 32, for "in" read into; and that the said LettersPatent should be read with this correction therein that the same mayconform to the record of the case in the Patent Office.

Signed and sealed this 29th day of September, A. D. 1936.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

